Site MapHelpFeedbackRNA Interference
RNA Interference

Why does control of gene expression usually occur at the transcription stage rather than the translation stage? Protein synthesis is a two stage process. DNA is used to produce mRNA (transcription) and then mRNA is used to produce proteins (translation). Transcription factors are a wide variety of molecules that control the production of mRNA. Factors that control the rate of translation are less well known – one is described in this animation. Unlike DNA, messenger RNA is a relatively short-lived molecule. If it is not used then it will probably break down shortly. Controlling the production of mRNA rather than its use, once produced, is probably a more efficient use of cellular resources.

View the animation below, then complete the quiz to test your knowledge of the concept.

1RNA intereference is a mechanism for silencing gene expression at the
A)level of replication.
B)level of transcription.
C)post-transcriptional but pre-translational level.
D)level of translation.
E)post-translational level.

2The protein ________ acts as an endonuclease in the first step of RNA interference.

3RNA interference is stimulated in the presence of ________ in the cell.
A)single-stranded RNA
B)double-stranded RNA
C)single-stranded DNA
D)double-stranded DNA

4RISC is an RNA-protein complex that binds to cellular mRNAs.

5Antisense mRNA can be produced during the life cycle of all viruses.

Animation Quiz SiteOnline Learning Center

Home > Biology 1 > Chapter 17 > RNA Interference